ABSTRACT Support is requested for a Keystone Symposia conference entitled Inflammation, Microbiota and Cancer, organized by Drs. Giorgio Trinchieri, Jenny P.Y. Ting, Hsing-Jien Kung and Jennifer A. Wargo. The conference will be held in Taipei, Taiwan from May 17-21, 2020. The concept of inflammation being linked to tumor promoting and even initiating a tumor microenvironment has evolved to include a complex network of interactions: innate and acquired immune response to the tumor; metabolism in tumor and immune cells; local and systemic effects of the microbiota on tumor predisposition, promotion, response to chemotherapy, radiotherapy, and immune therapy; and finally cancer co-morbidities and therapeutic side effects. The metabolic tumor environment affects innate and immune cell metabolism and activity thus modulating tumor progression and the response to therapy, particularly immunotherapy, but also chemotherapy and radiotherapy. Innate signaling also affects the tumor microenvironment and a complex cross-talk involving innate receptors, trained immunity, and class I Major Histocompatibility Complex (MHC) regulates both inflammation and anti-tumor immunity. Also, rapid progress in experimental animals and more recently in cancer patients, is unraveling a complex interaction between the microbiota at epithelial surfaces and within the primary tumor and metastatic sites with response to therapy. This, in turn, is raising the hope to be able to predict patient response to different types of therapy and to target the microbiota for improving therapy response, decreasing toxicity and preventing co-morbidity. The new scientific areas that will be covered during this conference will bring together aspects of cancer biology and immunity that are often only discussed at separate specialized meetings. The presence of both basic and clinical investigators will expose the participants to these new concepts. This conference will also provide an opportunity to discuss and explore the clinical translation of this rapidly emerging new understanding of cancer immunobiology. Finally, as there is a growing interest regarding health differences that adversely affect ethnically distinct and/or disadvantaged populations, an afternoon workshop, entitled Effects of Race and Ethnicity on Microbiome: Impacts on Cancer Health Disparities will be incorporated into the conference program.